NIOSH Studies What Boots Do to Firefighters

Dec 23, 2008

How much it takes out of a firefighter to work in heavy boots is an interesting question being explored by the National Institute for Occupational Safety and Health's laboratories in Morgantown, W.Va., and Pittsburgh, Pa. Specifically, the study of the physiological and biomechanical effects of boots' weight on male and female firefighters could help to reduce injuries among the approximately 1.1 million men and women who work as firefighters nationwide, the agency said.

About 25 percent of the 80,100 occupational injuries estimated among the firefighter population in 2007 by the National Fire Protection Association resulted from overexertion, and another 25 percent from falls. Most firefighters wear either heavily insulated rubber boots or leather boots, with the rubber boots being three pounds heavier than leather but generally costing about half as much.

The tests involved subjects wearing randomly assigned rubber or leather boots or safety shoes and being tested for oxygen consumption, joint movement, and walking patterns as they walked on a treadmill or climbed a revolving staircase while carrying a hose. For both tasks, oxygen consumption and heart rate were significantly greater when wearing rubber boots than when wearing leather boots.

"The preliminary findings from the study, which have been reported as work in progress at several scientific conferences, suggest that fire fighters adjusted their walking patterns and postures when wearing heavy firefighter boots. They walked slower, took wider steps, and for each stride they took, the percentage of time when both feet were in contact with the floor was longer with heavier boots, suggesting that they need more time to balance their body during walking," NIOSH reported. "Female firefighters tended to walk slower and take smaller steps than male fire fighters. The gender differences in gait patterns emphasize the importance for including female subjects in the study. In other preliminary findings of this study, boots weight was found to affect the way study participants naturally move their lower bodies. The boots limited fire fighters’ ankle, knee, and hip motions, and such restrictions may affect their ability to perform tasks efficiently, such as maintaining balance or crossing obstacles effectively during firefighting."

NIOSH said further research will investigate the effects of different types of firefighter boot soles and the effect of boot weight on walking over obstacles.